Various surgical procedures require the surgeon to access the thoracic region of a patient. A known approach to access the thoracic region is to cut the sternum in two parts and separate these two parts from each other for gaining access to the thoracic region. After completion of the surgical procedure, the separated parts of the sternum are brought back to their initial positions and fixed, for example, with a bone plate attached to the sternum parts or a wire tensioned around the circumference of the sternum.
U.S. Pat. No. 5,417,698 discloses a closure element to be looped around a human sternum. The closure element comprises a strap which is inserted through and retained by a tightening plate.
U.S. Pat. No. 8,460,295 discloses a sternum repair device including a central body and a plurality of bands extending from the central body. The bands are wrapped around the sternum to keep the sternum parts together. The central body includes a view window which is used by a surgeon to line up the device during installation on the sternum.
U.S. Pat. No. 8,486,114 discloses a cerclage system including a cable that encircles the sternum parts and a bone plate having channels to receive segments of the cable. The bone plate further includes a pair of locking studs to lock the cable within the channels to the bone plate.
EP 0 608 592 B1 discloses an assembly for banding a sternum. The assembly comprises an elongated flexible band, a needle at one end of the band and a buckle proximate the other end of the band. A main section of the band includes a plurality of spaced apart slots which can engage at a locking mechanism.
After the thoracic procedure such as, for example, a bypass operation has been carried out on a patient and the sternum parts have been fixed using a suitable fixation assembly, the patient is normally kept under surveillance. If it is detected that the surgical procedure has failed or that complications occur, it may be desirable for the surgeon to again open the fixation system for accessing the thoracic region. The time required for this opening procedure may be critical for the patient's health and even life.
In other situations, a cable or wire tensioned around the sternum parts (so-called “primary closure”) might become loose or break due to the load applied to the thoracic region of the patient. In such cases, the sternum part fixation may need to be stabilized by, for example, a bone plate (so-called “secondary closure”).
Similar or related problems occur in connection with other surgical procedure in which two or more bone parts need to be fixed.
There is a need for an implant for bone fixation that can be attached or separated fast, easily and at low risk for the patient. Furthermore, there is a need for such an implant which provides a high implant-bone-construct-stability. Moreover, there is generally a need for an implant for bone fixation that exhibits good surgical results.